1. Field of the Invention
The present invention relates to a taking lens system and an image pickup apparatus using the same.
2. Description of the Related Art
There have been known taking lens systems in which a plurality of lens units are moved for focusing onto an object at a very close distance. In such taking lens systems, the shooting distance to a very close object is reduced by moving a plurality of lens units. In this context, a very close object (or an object at a very close distance) refers to an object that is located at a position closer to the image pickup apparatus than the positions of close objects in the normal focusing range.
For instance, Japanese Patent Application Laid-Open No. 1-298307 discloses a taking lens system in which normal focusing operation is performed by moving the first lens unit having a positive refractive power toward the object side. In the taking lens system disclosed in Japanese Patent Application Laid-Open No. 1-298307, to effect focusing on a very close object, a lens unit arranged subsequent to the first lens unit is moved.
Japanese Patent Application Laid-Open No. 11-352402 discloses a taking lens system in which normal focusing operation at the telephoto end of the zoom range is performed by moving the third lens unit having a positive refractive power toward the image side. In the taking lens system disclosed in Japanese Patent Application Laid-Open No. 11-352402, to effect focusing on a very close object, the first lens unit and the second lens unit are moved.